Patient support with welded materials

ABSTRACT

Apparatus, systems, and methods to support a patient or other person include a first material that is substantially air impermeable welded to a second material that is substantially air permeable and liquid impermeable. The first material may also be liquid and vapor impermeable and the second material may be vapor permeable. Exemplary embodiments may include an inflatable enclosure formed from a sheet of the first material with an aperture, and the second material may cover a portion of the aperture.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 60/833,460, filed Jul. 26, 2006, which is incorporated by referenceherein without disclaimer.

FIELD OF THE INVENTION

The present disclosure relates generally to systems and methods forsupporting patients or other persons, and more particularly but not byway of limitation to systems and methods for supporting patients orother persons with materials that have been coupled or joined bywelding.

BACKGROUND

Patient support surfaces, including therapeutic surfaces, are common inmedical settings such as hospitals, clinics, and patients' homes, amongother places. Some surfaces (commonly referred to as “low air loss”surfaces) include inflatable enclosures that flow air through airpermeable materials adjacent to the patient in an effort to prevent ortreat pressure ulcers.

The treatment and/or prevention of pressure ulcers are serious andexpensive issues in the health care industry. Pressure ulcer developmentis related, in part, to the accumulation of heat and perspiration on theskin. Heat and moisture increase skin susceptibility to the damagingeffects of pressure and shear and decrease the resiliency of theepidermis to external forces. Ongoing compressive forces on skin tissuesare known to promote ischemia with subsequent development of pressureulcers. Therefore, controlling the microclimate of the skin andproviding a quality patient support system appear to be necessary toprevent pressure ulcers.

Low-air-loss (LAL) broadly refers to a system comprising a mattresscasing, a vapor permeable coverlet with or without lofting or cushioningmaterial, and an air delivery system to move air under the coverlet and,in some cases, to leak through the coverlet. Some LAL mattress systemsfunction as integral parts of patient support systems; whereas, othersare not actively coupled.

Currently, low-air-loss (LAL) mattress systems are the most prevalenttools used for pressure ulcer treatment and prevention. LAL mattresssystems were developed and are used in the belief that they help tocontrol the microclimate of the skin. These systems have been found tobe highly effective in treating and/or preventing pressure ulcers.

Certain support surfaces comprise more than one material, with eachmaterial having different air, vapor, and liquid permeabilityproperties. For example, it may be desirable to have a vapor permeablematerial adjacent to the patient's skin to allow moisture vapor totransfer away from the patient and into the support surface. It may alsobe desirable to have an air permeable material adjacent to the patient'sskin to allow air to flow proximal to the patient and assist in removingmoisture vapor from the patient and the support surface. Furthermore, itmay be desirable for portions of the support surface to be airimpermeable in order to restrict air flow and minimize powerrequirements and noise levels for the support system. For hygienicreasons, it may be desirable that the support surface comprise a liquidimpermeable material.

LAL mattresses typically include a foundation of a series ofinterconnected air cells that allow air to flow through and exit themattress. Other common elements include an adjustable pump that canmaintain air inflation of the air cells. In addition to the mattress,the LAL mattress system also includes the coverlet (waterproof and/orvapor permeable), and coverlet lofting material (e.g., quilted polyesterfabric batting) that attach over the mattress. The coverlet is typicallymade of one or more materials that are permeable to moisture, isimpermeable to bacteria, and is waterproof. Coverlets also function toprevent excessive loss of body heat, have high moisture vaporpermeability to minimize/prevent the accumulation of perspiration on theskin, and have high air porosity for removal of excessive body heatthrough a continuous airflow provided by the LAL mattress. Together, theLAL mattress and the coverlet form the LAL mattress system.

The LAL mattress can further include a fabric cover over the foundation(i.e., the air cells). In some cases, this fabric cover is formed from aGORE-TEX® fabric that is formed integrally with the air cells. TheGORE-TEX® fabric is liquid impermeable and has significantly higherair-permeable and vapor permeable characteristics as compared tourethane-backed nylon materials used in other mattresses. The GORE-TEX®fabric moisture vapor transfer characteristics help to prevent or speedup healing of pressure ulcers in patients by reducing the amount ofmoisture buildup on the skin and by helping to keep patients cooler byallowing body heat to more easily escape.

It is therefore desirable to construct a support surface from differenttypes of materials. As a result, it is often necessary to couple or joindifferent types of material used to form the support surface.

SUMMARY

Exemplary embodiments of the present disclosure are directed toapparatus, systems, and methods to support a patient or other person.Exemplary embodiments comprise a first air impermeable material weldedto a second material that is air permeable and liquid impermeable. Inexemplary embodiments, the first material is liquid and vaporimpermeable and the second material is vapor permeable. In exemplaryembodiments, an inflatable enclosure is formed from a sheet of the firstmaterial with an aperture, and the second material covers a portion ofthe aperture. In other exemplary embodiments, an inflatable enclosuremay be formed by several individual panels of the first material weldedto a panel of the second material.

Exemplary embodiments comprise a support member comprising an,inflatable enclosure having a first material and a second material,wherein the first material is substantially air impermeable, the secondmaterial is air permeable and substantially liquid impermeable, and thesecond material is welded to the first material. In exemplaryembodiments, the first material comprises an aperture and the secondmaterial covers a portion of the aperture. In other exemplaryembodiments, the second material is high frequency (HF) welded to thefirst material. In still other exemplary embodiments, the secondmaterial is vapor permeable. Certain exemplary embodiments comprise aninternal baffle. In still other exemplary embodiments, the firstmaterial is urethane. Certain exemplary embodiments comprise an openingconfigured to be coupled to a source of pressurized fluid.

Other exemplary embodiments comprise an apparatus for supporting aperson, comprising: a sheet comprising a first material, wherein thefirst material is substantially air impermeable; an aperture in thesheet; a second material covering the aperture, wherein the secondmaterial is air permeable and substantially liquid impermeable and thesecond material is welded to the first material. In certain exemplaryembodiments, the sheet comprises a first end, a second end, a first sideand a second side; the first side is coupled to the second side; thefirst end is sealed; and the second end is sealed, so that the sheet isconfigured to form an elongated inflatable enclosure. In exemplaryembodiments, the sheet is configured to form a generally cylindricalenclosure when inflated. Certain exemplary embodiments comprise aninternal baffle, wherein the elongated inflatable enclosure has across-section having a height and a width, wherein the height is greaterthan the width. In exemplary embodiments, the second material is highfrequency (HF) welded to the first material. In certain exemplaryembodiments, the second material is vapor permeable and/or the firstmaterial is urethane. In certain exemplary embodiments, the sheetcomprises an opening configured to be coupled to a source of pressurizedfluid.

Other exemplary embodiments comprise a support system comprising: aplurality of first and second support members, wherein the first supportmembers are a first height and comprise a first material that issubstantially air impermeable and the second support members are asecond height and comprise a second material that is air permeable andsubstantially liquid impermeable. In exemplary embodiments, the firstheight is greater than the second height and a second support member islocated between two first support members. In exemplary embodiments, thesecond material is vapor permeable. In certain exemplary embodiments,the first support members comprise a vapor permeable and liquidimpermeable third material. In other exemplary embodiments, a firstsource of pressurized fluid is coupled to the first support member andcoupled to the second support member. In still other exemplaryembodiments, a first source of pressurized fluid is coupled to the firstsupport member and a second source of pressurized fluid is coupled tothe second support member.

Other exemplary embodiments comprise a method of manufacturing a supportmember, the method comprising: providing a sheet of first material,wherein the first material is air impermeable; creating an aperture inthe sheet; covering a portion of the aperture with a second material,wherein the second material is air permeable and liquid impermeable;welding the second material to the first material; and configuring thesheet to form an inflatable enclosure. In exemplary embodiments, thesecond material is high frequency welded to the first material.

BRIEF DESCRIPTION OF THE FIGURES

While exemplary embodiments of the present invention have been shown anddescribed in detail below, it will be clear to the person skilled in theart that changes and modifications may be made without departing fromthe scope of the invention. As such, that which is set forth in thefollowing description and accompanying figures is offered by way ofillustration only and not as a limitation. The actual scope of theinvention is intended to be defined by the following claims, along withthe full range of equivalents to which such claims are entitled.

In addition, one of ordinary skill in the art will appreciate uponreading and understanding this disclosure that other variations for theinvention described herein can be included within the scope of thepresent invention. For example, exemplary embodiments are disclosed witha single sheet configured to form an inflatable enclosure. In otherexemplary embodiments, the inflatable enclosure may comprise multiplepanels coupled to form an inflatable enclosure. For example, exemplaryembodiments may comprise an inflatable enclosure with separate top,bottom, side and end panels.

In the following Detailed Description of Disclosed Embodiments, variousfeatures are grouped together in several embodiments for the purpose ofstreamlining the disclosure. This method of disclosure is not to beinterpreted as reflecting an intention that exemplary embodiments of theinvention require more features than are expressly recited in eachclaim. Rather, as the following claims reflect, inventive subject matterlies in less than all features of a single disclosed embodiment. Thus,the following claims are hereby incorporated into the DetailedDescription of Disclosed Embodiments, with each claim standing on itsown as a separate embodiment.

The following Figures are referenced herein. The Figures illustratingthe exemplary embodiments are not to scale.

FIG. 1 provides a top view of one exemplary embodiment of a supportsystem component according to the present disclosure.

FIG. 2 provides a side view of one exemplary embodiment of a supportmember according to the present disclosure.

FIG. 3 provides a cross-section view of one exemplary embodiment of asupport member according to the present disclosure.

FIG. 4 provides an end view of one exemplary embodiment of a supportmember according to the present disclosure.

FIG. 5 provides a top view of one exemplary embodiment of a supportsystem component according to the present disclosure.

FIG. 6 provides a side view of one exemplary embodiment of a supportmember according to the present disclosure.

FIG. 7 provides a cross-section view of one exemplary embodiment of asupport member according to the present disclosure.

FIG. 8 provides an end view of one exemplary embodiment of a supportmember according to the present disclosure.

FIG. 9 provides a top view of a one exemplary embodiment of a supportsystem according to the present disclosure.

FIG. 10 provides a side view of a one exemplary embodiment of a supportsystem according to the present disclosure.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Exemplary embodiments of the present disclosure are directed to anapparatus that functions as a patient support surface or therapeuticsurface formed from multiple materials that exhibit various propertiesand are joined at various locations using a welding technique to producea biologically sealed and controlled air loss surface. In certainexemplary embodiments, the welding technique used to couple or join thematerials is a high frequency (HF) welding technique. The materials maycomprise varying properties, including liquid, vapor, and airpermeability, as well as friction coefficients.

For example, in exemplary embodiments of the present disclosure, HFwelding, also referred to as dielectric welding or radio frequency (RF)welding can be used to join a urethane based material to apolytetrafluoroethylene (PTFE or Teflon)-based material such asGORE-TEX®, to form a support cushion having low-air-loss features,antimicrobial features, structurally sound features, and controlled airloss features, among others.

High frequency welding is a process that uses high frequency radioenergy to produce molecular agitation, and therefore heat, in varioustypes of materials so as to fuse the materials together. Thus, invarious embodiments, materials used to form support surfaces andtherapeutic surfaces of the present disclosure that are capable of beingHF welded are contemplated and are not limited to urethane basedmaterials and Teflon based materials such as GORE-TEX®.

Exemplary embodiments of the process involve subjecting the materials tobe fused or joined to a high frequency (between ˜13 and ˜100 MHz)electromagnetic field, which is normally applied between two metalsurfaces (e.g., metal bars). These surfaces also function as pressureapplicators during heating and cooling. The electromagnetic field causesthe molecules in polar thermoplastics to oscillate and thus, dependingon their geometry and dipole moment, these molecules may translate someof this oscillatory motion into thermal energy and cause heating of thematerial and eventually, the joining or fusing of the material.

HF welding is useful for joining polymers that have strong dipoles, suchas polyvinyl chloride (PVC), polyurethanes, and polyamides, amongothers. It is possible to RF weld other polymers including nylon,Polyethylene Terephthalate (PET), Ethylene Vinyl Acetate (EVA) and someAcrylonitrile Butadiene Styrene (ABS) resins, among others.

In various exemplary embodiments, other forms of welding are alsocontemplated. Hot gas welding, hot plate welding, ultrasonic welding,vibration or friction welding, laser welding, and solvent welding, amongothers may be implemented. As one of ordinary skill in the art willappreciate, some of these forms of welding might be more conducive towelding various plastics and other materials than other forms of weldingand thus, the types of materials to be welded to form a patient supportsurface and/or therapeutic surface of the present disclosure can bechosen based upon the form of welding desired or vice versa.

The Figures herein follow a numbering convention in which the firstdigit or digits correspond to the drawing Figure number and theremaining digits identify an element or component in the drawing.Similar elements or components between different Figures may beidentified by the use of similar digits. For example, an element in FIG.1 may be referenced as 110, and a similar element may be referenced as210 in FIG. 2. As will be appreciated, elements shown in the variousexemplary embodiments herein can be added, exchanged, and/or eliminatedso as to provide any number of additional embodiments of the supportmembers and support systems of the present disclosure.

Referring now to FIG. 1, a sheet 102 comprises an aperture 106. In theexemplary embodiment shown in FIG. 1, sheet 102 comprises a first end151, a second end 152, a first side 153, and a second side 154. Inexemplary embodiments, sheet 102 is comprised of a substantially airimpermeable material. In a particular exemplary embodiment, sheet 102 iscomprised of a material that is also substantially vapor and liquidimpermeable, such as urethane-backed nylon. As shown in FIG. 1, amaterial 104 covers aperture 106 (or a portion thereof). In exemplaryembodiments, material 104 is substantially air permeable. In certainexemplary embodiments, material 104 may be a substantially vaporpermeable and liquid impermeable material comprising PTFE, such asGoreTex®.

In the exemplary embodiment shown in FIG. 1, material 104 is welded tosheet 102 around the perimeter of aperture 106. In particular exemplaryembodiments, material 104 is welded to sheet 102 via a high frequencywelding process. In the exemplary embodiment shown, sheet 102 comprisesan opening 110 which may be connected to a source (not shown) ofpressurized air or other fluid.

In exemplary embodiments, material 104 may be sized so that it isslightly larger than aperture 106 and overlaps sheet 102 at theperimeter of aperture 106. In such exemplary embodiments, material 104may be lap welded to sheet 102. In other exemplary embodiments, material104 may be sized so that it is substantially the same size as aperture106. In such exemplary embodiments, a ring of backing material (notshown) may be placed at the junction of material 104 and sheet 102 toallow a butt-weld to be formed between material 104 and sheet 102. Incertain exemplary embodiments, the backing material may be comprised ofthe same material as sheet 102.

In the exemplary embodiment shown in FIG. 1, aperture 106 isapproximately centered between first side 153 and second side 154. Inthe exemplary embodiment shown in FIG. 1, aperture 106 also extendsalong a majority of the length of sheet 102.

Referring now to FIGS. 2 and 3, sheet 102 can be configured to form asupport member 100 that can be inflated with air or another pressurizedfluid. In the exemplary embodiment shown in FIGS. 2 and 3, sheet 102 hasbeen arranged so that first side 153 is coupled to second side 154. Inaddition, first end 151 and second end 152 have been sealed so thatsheet 102 forms an elongated enclosure. In exemplary embodiments, firstside 153 is coupled to second side 154 via welding to form a flat seamweld 114 and first end 151 and second end 152 are sealed via welding toform a pair of flat seam welds 112. In certain exemplary embodiments,first side 153 is high frequency welded to second side 154 and first end151 and second end 152 are sealed via high frequency welding. Inexemplary embodiments, opening 110 can be connected, for example, to anair pump (not shown) to move air into the support member 100 to bothinflate the support member 100 and to maintain a partial pressuredifference of vapor and thus, aid in moisture and heat removal from thepatient and from the environment surrounding the patient.

FIG. 3 illustrates a cross-section of FIG. 2 taken at section line 3-3.As shown in the exemplary embodiment of FIG. 3, support member 100 mayincorporate a baffle 116 that extends across support member 100. In thisexemplary embodiment, each end of baffle 116 is coupled to sheet 102 sothe cross-section of support member 100 is narrower than it is high. Inthe exemplary embodiment shown in FIG. 3, baffle 116 is sized so thatthe cross-section of support member generally forms an hourglass or“figure-8” shape with an indentation 117 at each side of support member100. The incorporation of baffle 116 provides a narrower cross-sectionfor support member 100 and allows for a greater number of supportmembers 100 to be incorporated into a patient support system.

FIG. 4 illustrates an end view of an exemplary embodiment of a supportmember 101 that does not incorporate a baffle. As shown, thecross-section of support member 100 in FIG. 4 is a generally circularshape. Other features are generally equivalent to those disclosed in thediscussion of FIG. 3.

Referring now to FIGS. 5-8, an exemplary embodiment of a support member200 comprises a lower portion 205 with a cap or upper portion 210.Exemplary embodiments of support member 200 are similar to those ofsupport member 100. However, exemplary embodiments of support member 200comprise a material 204 that is substantially air impermeable, ratherthan the air permeable material 104 used in support member 100. Inexemplary embodiments, material 204 is also vapor permeable and liquidimpermeable. In addition, exemplary embodiments of support member 200comprise an aperture 206 that is larger than aperture 106 of supportmember 100. In exemplary embodiments, aperture 204 extends substantiallyacross the entire length of support member 200 so that it is proximal tofirst end 251 and second end 252.

Similar to the construction techniques used to form support member 100,exemplary embodiments of support member 200 may be formed by welding afirst side 253 to a second side 254 and sealing first and second ends251 and 252. Material 204 may also be welded to sheet 202 to coveraperture 206 in exemplary embodiments.

In other embodiments, support member 200 may be constructed in othermanners. For example, support member 200 may comprise separate pieces ofmaterial, rather than a single sheet 202 with an aperture 206.

In the exemplary embodiment shown in FIG. 7, sheet 202 has been formedinto a support member with an hourglass or “figure-8” cross-section. Inthis exemplary embodiment, support member 202 incorporates a baffle 216.As shown in the exemplary embodiment of FIG. 8, sheet 202 may also beformed into a support member 201 that is generally cylindrical with acircular cross section in certain exemplary embodiments.

Referring now to FIGS. 9 and 10, an exemplary embodiment of a supportsystem 300 comprises a first set of support members 100 and a second setof support members 200. As shown in the top view of FIG. 9, supportmembers 100 and 200 are arranged in a generally alternatingconfiguration so that a support member 100 is located between twosupport members 200. Support members 100 and 200 may be inflated withpressurized air or another source of fluid.

As shown in the partial side view of the exemplary embodiment in FIG.10, support members 200 are taller than support members 100. Inexemplary embodiments, support members 200 are comprised of material 202that is substantially air impermeable with a cap of material 204 that isair impermeable and vapor permeable. In exemplary embodiments, supportmembers 100 comprise a material 102 that is air impermeable and a cap ofmaterial 104 that is air permeable and liquid impermeable. In exemplaryembodiments, support members 200 will provide primary support for aperson (not shown) laying on support member 300. In exemplaryembodiments, air can flow through support members 100 and exit material104 covering aperture 106. Such air flow can assist in transferringmoisture vapor from a person's body as they lay on support system 300.Air flow may also assist in removing moisture vapor from support members100.

In exemplary embodiments, moisture vapor may transfer from a personthrough material 204 and into support member 200. In the exemplaryembodiment shown in FIG. 9, material 204 extends nearly to edges 305 and310 of support system 300. Therefore, a significant portion of material204 will not be in contact with a person laying on support system 300.As a result, moisture vapor can also exit support member 200 viamaterial 204. In exemplary embodiments, increasing the area covered bymaterial 204 will increase the rate at which moisture vapor can betransferred from a person being supported by support system 300.

In the exemplary embodiment shown in FIGS. 9 and 10, support system 300is configured to reduce the amount of air flow needed to support aperson and provide moisture vapor transfer capabilities. Primary supportis provided by support members 200, which comprise material that issubstantially air impermeable, and therefore requires minimal air flowto remain inflated and provide support. Support members 100 comprisematerial 104 which is air permeable and therefore requires more airflowthan support members 200 to stay inflated. The amount of air (or otherpressurized fluid) required to inflate support members 100 and 200 canbe reduced because the air flow is restricted to areas covered bymaterial 104. In addition, the power requirements and noise levels ofequipment needed to inflate support members 100 and 200 are alsoreduced. In certain exemplary embodiments, support members 100 may becoupled to one source of pressurized fluid and support members 200 maybe coupled to a second source of pressurized fluid. In such exemplaryembodiments, each source of pressurized fluid can be configured to theoperating parameters required. For example, the source of pressurizedfluid for support members 100 may be a lower pressure, higher volumesource than the source of pressured fluid for support members 200.

In exemplary embodiments, support members 100 and 200 can be weldedtogether to form the contiguous patient support surface system 300. Inother embodiments, the support members 100 and 200 can be enclosed by acover (not shown) to form the contiguous patient support surface 300.

While exemplary embodiments have been shown and described in detailabove, it will be clear to the person skilled in the art that changesand modifications may be made without departing from the scope of theinvention. As such, that which is set forth in the foregoing descriptionand accompanying drawings is offered by way of illustration only and notas a limitation. The actual scope of the invention is intended to bedefined by the following claims, along with the full range ofequivalents to which such claims are entitled.

In addition, one of ordinary skill in the art will appreciate uponreading and understanding this disclosure that other variations for theinvention described herein can be included within the scope of thepresent invention. For example, the patient support surface can becoated with an antimicrobial agent, as are known or will be known.

In the foregoing Detailed Description, various features are groupedtogether in several embodiments for the purpose of streamlining thedisclosure. This method of disclosure is not to be interpreted asreflecting an intention that the embodiments of the invention requiremore features than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive subject matter lies in less than allfeatures of a single disclosed embodiment. Thus, the following claimsare hereby incorporated into the Detailed Description, with each claimsstanding on its own as a separate embodiment.

1. A support member comprising: an inflatable enclosure comprising afirst material and a second material, wherein: the first material issubstantially air impermeable; the second material is air permeable andsubstantially liquid impermeable; and the second material is welded tothe first material.
 2. The support member of claim 1 wherein the firstmaterial comprises an aperture and the second material covers a portionof the aperture.
 3. The support member of claim 1, wherein the secondmaterial is high frequency (HF) welded to the first material.
 4. Thesupport member of claim 1 wherein the second material is vaporpermeable.
 5. The support member of claim 1, further comprising aninternal baffle.
 6. The support member of claim 1 wherein the firstmaterial comprises urethane and the second material comprisespolytetrafluoroethylene.
 7. The support member of claim 1 furthercomprising an opening configured to be coupled to a source ofpressurized fluid.
 8. An apparatus for supporting a person, theapparatus comprising: a sheet comprising a first material, wherein thefirst material is substantially air impermeable; an aperture in thesheet; a second material covering the aperture, wherein the secondmaterial is air permeable and substantially liquid impermeable and thesecond material is welded to the first material.
 9. The apparatus ofclaim 8 wherein: the sheet comprises a first end, a second end, a firstside and a second side; the first side is coupled to the second side;the first end is sealed; and the second end is sealed, so that the sheetis configured to form an elongated inflatable enclosure.
 10. Theapparatus of claim 9, wherein the sheet is configured to form agenerally cylindrical enclosure when inflated.
 11. The apparatus ofclaim 9 further comprising an internal baffle, wherein the elongatedinflatable enclosure has a cross-section having a height and a width,wherein the height is greater than the width.
 12. The apparatus of claim8 wherein the second material is high frequency (HF) welded to the firstmaterial.
 13. The apparatus of claim 8 wherein the second material isvapor permeable.
 14. The apparatus of claim 8 wherein the first materialcomprises urethane and the second material comprisespolytetrafluoroethylene.
 15. The apparatus of claim 8 wherein the sheetcomprises an opening configured to be coupled to a source of pressurizedfluid.
 16. A support system comprising: a plurality of first supportmembers, wherein: the first support members comprise a first materialthat is substantially air impermeable; and the first support members area first height; and a plurality of second support members, wherein: thesecond support members comprise a second material that is air permeableand liquid impermeable; the second support members are a second height;the first height is greater than the second height; and a second supportmember is located between two first support members.
 17. The supportsystem of claim 16 wherein the second material is vapor permeable. 18.The support system of claim 16, wherein the first support memberscomprise a third material and the third material is vapor permeable andliquid impermeable.
 19. The support system of claim 16, furthercomprising a first source of pressurized fluid coupled to the firstsupport member and coupled to the second support member.
 20. The supportsystem of claim 16, further comprising a first source of pressurizedfluid coupled to the first support member and a second source ofpressurized fluid coupled to the second support member.
 21. A method ofmanufacturing a support member, the method comprising: providing a sheetof first material, wherein the first material is air impermeable;creating an aperture in the sheet; covering a portion of the aperturewith a second material, wherein the second material is air permeable andliquid impermeable; welding the second material to the first material;and configuring the sheet to form an inflatable enclosure.
 22. Themethod of claim 21 wherein the second material is high frequency weldedto the first material.